What is normal TTTG?
Several studies suggest that a normal TT-TG distance is 10 mm or less [5, 7, 8]. A TT-TG distance greater than 15 mm in patients with patellofemoral insta- bility may predict limited benefit from phys- ical therapy [7].
What is TTTG in knee?
The TT-TG distance represents the radiographic measurement of the quadriceps vector, which represents a lateral force displacement on the patella during knee motion. It is > 20 mm in patients with recurrent patellar dislocations, as compared with 13 mm in control subjects.
What is a Trochleoplasty?
• Trochleoplasty is a surgical procedure that creates a groove in the trochlea to. prevent recurrent patella dislocations, and the associated pain and disability. • The procedure will be performed under a general anaesthetic.
How is Trochlear depth measured?
The trochlear depth is calculated by measuring the mean of the maximum anteroposterior (AP) distance of the medial and lateral femoral condyles minus the distance between the deepest point of the trochlear groove and the line paralleling the posterior femoral condyles surfaces (Fig. 1).
How is TTTG distance calculated?
Draw a line along the posterior femoral condyles, and then draw the following lines perpendicular to this line:
- bisecting the tibial tuberosity (TT)
- bisecting the trochlear groove sulcus (TG)
- measure the distance between TT and TG = TT-TG distance.
What is patellar instability?
The patella (kneecap) attaches to the femur (thigh bone) and tibia (shin bone) by tendons. The patella fits into a groove at the end of the femur (trochlear groove) and slides up and down as the knee bends and straightens. Patellar instability occurs when the kneecap moves outside of this groove.
How do you measure TTTG?
How common is Trochleoplasty?
Description of a Trochleoplasty A trochleoplasty is a rare procedure that is performed in patients that have type B or type D trochlear dysplasia. In these patients, the trochlea can be either flat or dome shaped, which results in severe instability of the patellofemoral joint.
How do you fix trochlear dysplasia?
Trochleoplasty is indicated mainly for high-grade trochlear dysplasia. In the majority of these cases, trochleoplasty is performed in association with other procedures (such as anterior tibial tubercle [ATT] transfer or medial patella-femoral ligament [MPFL] reconstruction).
How is trochlear dysplasia diagnosed?
Trochlear dysplasia is best diagnosed on both a 45-degree patella sunrise view and also on the lateral x-rays. On the lateral knee x-rays, the femoral condyles may not overlap normally and there can be what is called a crossing sign, which indicates the trochlea is not fully developed.
Is patella alta painful?
This condition is called “chondromalacia” which means softening of the cartilage. It is painful and is the first sign of damage to the joint surface. If the process continues it will result in bone articulating on bone with serious osteoarthritis which may require joint replacement.
What is lateral subluxation of the patella?
A patellar subluxation means that the kneecap has briefly slid out of its normal place in that groove. In most cases the kneecap moves towards the outside of the body when it slides out of place. This can be a one-time event, or it can happen multiple times.
How reliable is tttg on MRI and CT scans?
The mean TTTG referenced on cartilaginous landmarks was 15.3+/-4.1 mm on CT scans, and 13.5+/-4.6 mm on MR images. An excellent interrater (82%), intermethods (86%), and interperiod (91%) quantitative reliability was found. TTTG can be determined reliably on MRI using either cartilage or bony landmarks. Additional CT scans are not necessary.
What is TT-TG in patella?
Tibial tuberosity-trochlear groove (TT-TG) distance is important in the assessment and treatment of patellofemoral disorders. However, normal and pathological TT-TG values have not been established in Koreans.
How reliable is TT-TG distance measurement on rotational profile CT?
Interobserver and intraobserver reliability of TT-TG distance measurements was good. The median TT-TG distance for this Korean population was 11.24 mm (mean, 10.24 ± 0.8 mm). TT-TG distance measured nearly 2 mm less on rotational profile CT scans. Conclusions
What is tttt-TG distance?
TT-TG distance is a measurement derived from CT or MRI scans, which gives an indication of the sideways alignment of the groove in which the kneecap slides with the attachment point of its tendon on the tibia. TG = trochlear groove, and for the measurement it is identified at its deepest point. TT = tibial tubercle, where the tendon attaches.